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Journal of Electromagnetic Analysis and Applications 2022年第8期14卷 89-103页

作者： Gora Diop Ousmane Sow Moustapha Thiame Richard Mane Ibrahima Diatta Khady Loum Sega Gueye Mamadou Wade Gregoire Sissoko Ecole Polytechnique de Thiès Thiès Senegal Institut Universitaire de Technologie Université Iba Der THIAM de Thiès Thiès Senegal Université Assane SECK Zinguinchor Senegal groupe international de recherche en energie renouvelable(GIRER) Dakar Sénégal

The diffusion coefficient of the minority charge carriers in the base of a silicon solar cell under temperature and subjected to a magnetic field, passes in reso-nance at temperature (Topt). For this same magnetic field, the diffusion coeffi-cient of the photogenerated carriers by a monochromatic light in frequency modulation enters into resonance, at the frequency (ωc). Under this double resonance in temperature and frequency, the diffusion coefficient is used in the expression of the recombination velocity of the minority charge carriers on the back side of the base of the solar cell (n+/p/p+), to obtain, by a graphical method, the optimum thickness. A modeling of the results obtained shows a material saving (Si), in the development of the solar cell.

关键词： Silicon Solar Cell-Diffusion Coefficient Recombination Velocity Absorption Coefficient Magnetic Field-Temperature-Thickness

Solar Controller with Automatic Search Technology for the Maximum Power Point with Autonomy Display

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energy and Power engineering 2022年第9期14卷 509-522页

作者： Mamadou Sall Ousmane Sow Sega Gueye Gora Diop Lemrabott Habiboullah Mamadou Wade Gregoire Sissoko Ecole Polytechnique de Thiè s Thi&egrave s S&eacute né gal Institut Universitaire de Technologie. Université Iba der THIAM de Thi&egrave s S&eacute né gal groupe international de recherche en energie renouvelable(GIRER) Dakar S&eacute né gal Ecole Supérieure Multinationale de Té lé communication Dakar S&eacute né gal

In our work, we have been interested in conducting technological research on the use of photovoltaic energy for lighting. In fact, we have produced a stand-alone photovoltaic system with automatic search for the maximum power point, consisting of a photovoltaic module, a solar regulator, a storage battery and a digital control by microcontroller. The solar field is connected to the input of the regulator and the battery to its output. When the battery voltage is lower than the regulation voltage, the controller operates the photovoltaic generator at maximum power Pmpp and transfers this power to the output. In addition to the protection function, this regulator ensures tracking of the maximum power point (MPPT) and allows the photovoltaic generator to deliver its power whatever the variation of climatic conditions (sunshine and temperature). The main role of the solar regulator is the continuous monitoring of the state of charge of the battery to ensure its protection against overcharging and excessive discharging, the coupling and decoupling of the user as well as its maintenance. The principle of operation is based on controlling a DC-DC converter by a rectangular “PWM” signal generated by a PIC16F874 microcontroller which also controls the entire system. The results of simulation after realization were presented to illustrate the operation of the regulator by curves.

关键词： Index Terms-Battery Charge/Discharge Regulator PIC16FC874

Influence of Heat Exchange Coefficients on Both Optimized Thermal Contact (OTCR) and Critical (CTCR) Resistances at the Contact Interface of a Flat Concrete Slab and a Rice Straw Board

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energy and Power engineering 2021年第12期13卷 392-402页

作者： Alassane Diene Mamadou Lamine Lo Abdoulaye Sene Ablaye Fame Youssou Traore Seydou Faye Issa Diagne Mamadou Babacar Ndiaye Gregoire Sissoko Polytechnic School of Thiès Thiès Senegal Laboratory of Semiconductors and Solar energy Physics Department Faculty of Science and Technology University Cheikh Anta Diop Dakar Senegal University Institute of Technology University Iba Der THIAM of Thiès Thiès Sénégal groupe international de recherche en energie renouvelable Dakar Senegal

The study is carried out in imperfect contact with a concrete slab wall attached to a panel based on rice straw compressed in a dynamic frequency regime. We will propose the characterization of thermal insulation for thermal resistance of contact (x = 0.05 m). The impact of heat exchange coefficients on the front face (x = 0 m) and the rear face (x = 0.1 m) on these resistors is shown.

关键词： Concrete Slab Rice Straw Board Thermal Resistance of Contact Frequency Dynamic

Effects of the number of particles and coordination number on viscous-flow agglomerate sintering

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Particuology 2019年第2期17卷 76-83页

作者： Mohammadmahdi Kamyabi Khashayar Saleh Rahmat Sotudeh-Gharebagh Reza Zarghami Multiphase Systems Research Laboratory School of Chemical Engineering College of Engineering University of Tehran Tehran 11155/4563 Iran Sorbonne University/Compiegne University of Technology EA 4297 Transformations Integrees de la Matiere renouvelable France

The process of sinteri ng of several particles in con tact via a viscous flow mecha nism was studied numerically using computational fluid dynamics. The volume of fluid technique within a finite volume method was used to simulate bridge formation between particles, as well as densification at different configurational states of the particles. The method was validated by comparing results for two-particle coalescence with the *** effect of the numberof particles on agglomerati on kin etics was studied by comparing bridge growth rate for systems having different numbers of particles in a chain. Although increasing the number of particles led to a decrease in the local bridge growth rate and to slower equilibration, there were no marked differences, when the overall volume of the system was considered. The effect of coordination number on the densification rate was directly studied by changing the number of particles in contact with a central *** the coordination nurnbec caused the overall rate of densificatio n to in crease, but delayed equilibration, analogous to steric effects. These findi ngs describe the con figurational state of agglomerates, typical of mesoscale caking. In a multi-scale study, they can be used to characterize caking at a bulk scale to partly address the lack of experimental data in this field.

关键词： Caking Agglomeration Sintering Viscous flow mechanism Volume of fluid Coordination number

Evaluation of the Performances of the First Grid-Connected Photovoltaic System in Sénégal

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international Journal of Clean Coal and energy 2020年第1期9卷 1-14页

作者： P. W. Tavares H. D. Ndiath M. Kane B. Mbow A. T. Niang I. Youm Laboratoire des Semi-Conducteurs et d’energie Solaire (LASES) Département de Physique Faculté des Sciences et Techniques Université Cheikh Anta Diop de Dakar Sénégal Centre d’Etudes et de recherches sur les energies renouvelable (CERER) BP 476 Dakar Université Cheikh Anta Diop Dakar Sénégal

This document presents the evaluation and the monitoring of the performances of the first grid-connected photovoltaic system installed in the Center of Studies and Researches on the Renewable energies (CERER) inaugurated on december 4th, 2012 by the governmental authorities of Senegal and Tenerife. This mini power plant of 3.15 kWc is a perfect example of the political will of the government which is to reduce the production cost of the electricity, with the diversification of the sources of production, and the greater use of the other sources such as the natural gas, the coal, the renewable energies. The evaluation of the performances of the installation is realized by using the indicators of efficiency and performance as the photovoltaic surface yield, the ratio of photovoltaic performance, the photovoltaic specific yield, and the losses of captures. The obtained results show that a big part of the energy shone during the period of observation was not able to be used further to circumstances such as the losses of conductivity, the heat losses or for example the defects on components. The analysis also shows that a large part of the produced energy is not injected because of the dilapidation of the network, the defects of landing but especially one disjunction sees frequently at the level of the point of injection.

关键词： Analysis of the Performances The Photovoltaic Solar energy Grid-Connected PV System Senegal